LIFECODES is an ongoing prospective birth cohort conducted at Brigham and Womens Hospital in Boston, MA by Dr. Thomas McElrath. Begun in 2006, this study aims to investigate environmental contaminants associated with adverse pregnancy outcomes, isolate mechanisms underlying their associations, and identify predictors that can be used for prevention. Within this cohort there are several research projects which exist to address more specific research questions. Bisphenol A and Phthalate Exposure in Relation to Fetal Growth and Preterm Birth (R01ES018872; PI John Meeker) was developed to study environmental risk factors for adverse effects on fetal growth and preterm birth. The study measured urinary phthalate metabolites as well as biomarkers of inflammation, oxidative stress, and endocrine disruption of cases of preterm birth as well as controls from the LIFECODES cohort recruitment from 2006-2008. The primary research objectives were to assess the relationship between maternal exposure to phthalates and BPA exposure measured at up to four visits per subject during pregnancy in relation to preterm birth as well as fetal growth, as assessed by repeated ultrasound measures. Additionally, the study sought to explore biological mechanisms underlying these associations and identify windows of susceptibility to exposure. At NIEHS we have utilized this existing data and added to it in several ways. First, as a pilot study in the Childrens Health Exposure Assessment Resource (CHEAR) program, we analyzed urinary trace metals as well as metabolomics in urine specimens from the 3rd trimester of pregnancy from the participants of the preterm birth case-control study described above. The objectives of this project were to examine each individual trace metals as well as metal mixtures in relation to: 1) overall preterm birth (delivery <37 weeks gestation) as well as preterm birth subtypes (spontaneous and placentally mediated); 2) fetal growth as assessed by ultrasound measures in pregnancy; and 3) urinary oxidative stress biomarkers that were also measured at that time point. Additionally, we sought to examine metabolomics profiles as potential mediators of these associations. The second project under the LIFECODES study is an investigation of the association between consumer product chemical exposure in pregnancy and their cumulative impact on disorders of fetal growth. Last years progress The major progress this year has been under the first project described above. We investigated associations between urinary trace metals individually as well as in mixtures in association with preterm birth as well as preeclampsia. In addition, we have investigated several related questions using this data. Under the second project described above, we have collected pilot data and are preparing a larger case-cohort study to investigate our research questions.